Watchman s clock



(No Mdel.)

G. W. & A. D. BLODG-TT.

'Watohmans Clock.

N0. 240,647. Patented April 26, |881.

r f/flflfllll l i UNITED STATES PATENT OEEICE.

GEORGE W. BLODGETT, OF BOSTON, AND AARON l). BLODGETT, OF NEWTON, ASSIGNORS TO THEMSELVES, JAMES E. STONE AND GEO. H. VOODRUFF, OF BOSTON, AND JAMES F. EMERSON, OF VAKEFIELD, MASSACHUSETTS.

WATCHMANS CLOCK.

SPECIFICATION forming part of Letters Patent No. 240,647, dated .April 26, 188i.

Application tiled January 20, 1881. (No model.)

To all whom it may concern:

Beitkuown that we, GEORGE W. BLoDGE'r'r, ot" Boston, in the county ol" Sut't'olk and State ot' Massachusetts, and AARON l). BLoDeE'r'r, ot' Newton, in the county ot' Middlesex and said State, have invented an Improved latchmans Clock, ot' which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, making a part ot' hereof, in which- Figure l is a diagram illustrating ourinvention. Fig. 2 is a horizontal central section of the clock shown in Fic'. l. Fig. 3 is a sectional View enlarged. Fig. 4 is a modification.

Many plans have been devised for enabling employers to make sure that watchmen and others have been vigilant or have faithfully discharged their duty, and our invention relates to contrivances ot' this class; and it consists in the combination ot' a time-piece and one or more electrical bells or other signals in such a manner that the time of striking of the bells or giving the signals can be predetermined by the employer and readily changed at pleasure, but can only be ascertained by the watchman by vigilance, so that it' the watchman be required to keep a record ot' the time when the signal is given, or time and place where there are more than one signal, such record'will readily show whether he has been vigilant or not.

In the drawings we have shown four bells, A B C D, which are supposed to be at different rooms of a factory, (although, as is obvious, the number and arrangements of the bells or other signals will va'ry very largely,) all in one electrical circuit a ct, 85o. This circuit is open normally, and the hammer of each bell remains away from its bell until the circuit is closed, although, as will be clear, the circuit might be a closed circuit and the alarm or signal be given by breaking the circuit instead of making it. Under these circumstances if the watchmans duty be to visit the four rooms ot' the factory from time to time during the night and to keep a record of the time when he is in each room, and also to keep a record ot' the time when each bell strikes, it is clear that he cannot keep a true record unless he knows just when each bell will strike, and it' the appara- 5o tus be so set that the bells will strike at irregular but predetermined intervals, a true record is impossible unless the watchman is vigilant. and notes the signals and the time when each sounds, and in this case the place where or room in which each sounds. The principle ci' our invention consists, therefore, in the use ot' one or more alarms or signals which signal at intervals known to the employer, but unknown to the person employed, the record ci" the sig- 6o nals by the employe showing conclusively whether he has done his duty or not.

The simplest form of our apparatus is that shown in detail in Fig. 2 ofthe drawings,

where F represents a time-piece, upon the main clock, and as the wire a2 is in electrical contact 7 5 with the metal frame of the clock, the circuit is made whenever spring g comes in contact with either ofthe pins h. Now, if the disk j be provided with a given number ot' pins, say

at regular intervals, the mere motion of disk 8o j' at the hour-hand rate will cause the times ot' contact to vary; for suppose there be but four pins lz., then itl the diskj' did not revolve the spring carried by the min utc-han d would make contact once every quarter ot' an hour, and if S5 the lirst contact was on the hour the next would be on the quarter, the next on the halt', and the third on the three-quarters, and so on; but as the disk j" revolves at the hour-hand rate the second contact, supposing the irst to 9o be on the hour, will be at nearly seventeen minutes past, the second contact will be about thirty-three minutes past, and so on, each contact and each signalbeing thus rendered irregular. The disk j' is provided with a number of holes, so that the pins h can be shifted to various positions and their number varied from time to time, for in a few days an intelli gent Watchman will soon learn, especially it' he keeps a careful record, the true order of the signals; but if the position or both the position and number of the pins 7L be varied from time to time, it will at once be seen Whether he is faithful or not. As an additional precaution a second series ot' pins h are used, which are inserted in a metallic ring, 7c, secured to thedial,or in proper relation to a-second spring g on the minute-hand. This ring may be readily revolved by the mechanism ofthe clock in a manner too well known to require descrip tion.

It will be obvious that our system may be largely modified, and that the number of bells and contact-pins will vary with the number of stations for example, in one case, a machine required to be attended to about tive times an hour during the night, and in this case the faithful performance ot' the attendants duty was secured by a clock having tive pins on the disk fand but one bell in the circuit, the second series of pins being` unnecessary in this instance.

In some instances it is desirable to have one of the springs g the electrode ot' one circuit and the other spring the electrode otl a diii'erent circuit. This is readily accomplished by attaching insulated rings of metal to the minute-hand arbor, as shown in Fig. 4, each ring being connected by a light spring to its own circuit.

Wle have spoken mainly of Watchmen, but it will be clear that our clock is useful in hospitals and other places for the proper serving ot` prescriptions, in greenhouses and other places t'or the proper regulation ot' the temperature, and for many like purposes.

What we claim as our invention is The watchmans clock above described, consisting' of a time-piece having pins h inserted at the face ot' the clock, in order that they may be readily changed in number and position, or both, each pin being in electrical connection with circuit a a, and also provided with one or more contact-springs, g, also connected with circuit a a', whereby contact between springg and any one ot' the pills lt completes circuit a a and gives one or more signals, all as above set i'orth.

GEO. W. BLODGET". AARON l). BLODGET".

Witnesses J. E. MAYNADIER, JonN lt. Snow. 

